Represents unvested restricted shares of the issuer's common stock which were relinquished by the reporting person (and canceled by the issuer) in exchange for cash payments totaling $543,375 to be made to the reporting person in two equal installments on December 31, 2011 and December 31, 2012.

(2)

The two reported transactions involved an amendment of an outstanding option, resulting in the deemed cancellation of the "old" option and the grant of a replacement option. The option, which was originally granted on July 20, 2005, was amended solely to change its expiration date from July 20, 2015 to November 25, 2011.

(3)

The two reported transactions involved an amendment of an outstanding option, resulting in the deemed cancellation of the "old" option and the grant of a replacement option. The option, which was originally granted on July 19, 2006, was amended solely to change its expiration date from July 19, 2016 to November 25, 2011.

(4)

The two reported transactions involved an amendment of an outstanding option, resulting in the deemed cancellation of the "old" option and the grant of a replacement option. The option, which was originally granted on May 21, 2008, was amended solely to change its expiration date from May 21, 2015 to November 25, 2011.

(5)

The vesting date of the option was previously accelerated by the compensation committee of the issuer's board of directors from May 21, 2013 (or earlier under certain circumstances) to October 26, 2011.

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